1. Field of the Invention
The invention relates to a position-regulating device for working mechanisms of mobile machines and a method of regulating the position of working mechanisms of mobile machines.
2. Discussion of the Prior Art
A micro-mechanical incline sensor, in particular for motor vehicles, is known as such from DE 197 52 439 A1, and has a bearing plate, the inclination of which is determined relative to the horizontal. At least two pressure sensor units are integrated on the bearing plate to determine a pressure applied to the plate at the respective points. An earth plate is connected to the bearing plate via the pressure sensor units. An evaluation unit uses the data produced by the pressure sensor units to determine the inclination of the bearing plate relative to the horizontal. Depending on the inclination of the device in which the inclination sensor is integrated, the earth plate applies a different degree of force to the respective sensor unit. At least two pressure sensors must be provided in order to measure the angle of inclination. In DE 197 52 439 A1, these are provided in the form of piezo-resistive pressure detectors.
A level-regulating device for a quay crane is known from DE 39 38 766 A1. In this case, levelling is regulated using a hydraulic control valve to actuate one or more hydraulic actuators for a part which is to be maintained at a specific level, the part being coupled with another part by which it can be adjusted to any position. To ensure a high degree of operating safety without using expensive electronic systems, the control valve is mechanically linked to and actuated by a pendulum, as its operating mechanism, the position of which is determined by gravity.
When the device is at an incline, the pendulum effects a damped deflection in a fixed direction in space, which is transmitted via the control valve to the hydraulic actuator. In DE 39 38 766 A1, a loading and unloading crane, particularly one which is suitable for loading and discharging ships, fitted with this feature, is set up so that when the crane boom is raised and lowered, a loading and unloading device disposed thereon remains in a fixed position relative to the rest of the structure.
One particular disadvantage of the level-regulating device known from DE 39 38 766 A1 is the one-dimensional orientation. In the embodiment described as an example in the above-mentioned patent specification of providing a levelling means on a loading and unloading crane, preferably used for ships, the device is totally satisfactory but for mobile machinery such as earth moving machines, for example, which preferably have to move around building sites and hence on uneven ground, one-dimensional level correction is not sufficient.